$ wget --user-agent="Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; WOW64; SLCC1; .NET CLR 2.0.50727; .NET CLR 3.0.04506; .NET CLR 1.1.4322; InfoPath.2)" -
d -Outub_4.xml "http://v3.lscache3.googlevideo.com/videoplayback?sparams=id%2Cexpire%2Cip%2Cipbits%2Citag&itag=5&ip=24.5.195.167&signature=94C6945EFCA34A30A6CD
A6EA7AB6CFA13D8055B8.0129187173974171D38CB83145B09223B55D346C&sver=3&expire=1241236858&key=yt1&ipbits=0&id=545195cededce5b6"

Setting --output-document (outputdocument) to utub_4.xml
DEBUG output created by Wget 1.11.3 on cygwin.

--2009-05-01 15:58:45--  http://v3.lscache3.googlevideo.com/videoplayback?sparams=id%2Cexpire%2Cip%2Cipbits%2Citag&itag=5&ip=24.5.195.167&signature=94C6945EFCA3
4A30A6CDA6EA7AB6CFA13D8055B8.0129187173974171D38CB83145B09223B55D346C&sver=3&expire=1241236858&key=yt1&ipbits=0&id=545195cededce5b6
Resolving v3.lscache3.googlevideo.com... 74.125.15.22
Caching v3.lscache3.googlevideo.com => 74.125.15.22
Connecting to v3.lscache3.googlevideo.com|74.125.15.22|:80... connected.
Created socket 4.
Releasing 0x00ee1278 (new refcount 1).

---request begin---
GET /videoplayback?sparams=id%2Cexpire%2Cip%2Cipbits%2Citag&itag=5&ip=24.5.195.167&signature=94C6945EFCA34A30A6CDA6EA7AB6CFA13D8055B8.0129187173974171D38CB83145
B09223B55D346C&sver=3&expire=1241236858&key=yt1&ipbits=0&id=545195cededce5b6 HTTP/1.0
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; WOW64; SLCC1; .NET CLR 2.0.50727; .NET CLR 3.0.04506; .NET CLR 1.1.4322; InfoPath.2)
Accept: */*
Host: v3.lscache3.googlevideo.com
Connection: Keep-Alive

---request end---
HTTP request sent, awaiting response...
---response begin---
HTTP/1.1 200 OK
Content-Disposition: attachment; filename="video.flv"
Last-Modified: Sat, 17 May 2008 01:28:32 GMT
Content-Type: video/x-flv
Content-Length: 4005432
Expires: Fri, 01 May 2009 23:58:46 GMT
Cache-Control: public,max-age=3600
Connection: close
Date: Fri, 01 May 2009 22:58:46 GMT
Server: gvs 1.0

---response end---
200 OK
Length: 4005432 (3.8M) [video/x-flv]
Saving to: `utub_4.xml'

100%[======================================================================================================================>] 4,005,432   92.6K/s   in 30s

response from call #2 has "Location:" in the headers . See the '303' response, the direct location in cache that could be requested by client ( no token req'd ). This request does not need a token . It calls the cache.

youtube call 3 - get the actual video steam/file directly from the cache

Bash